Temporary fix for bad label size on Linux

In particular, KDE with QtCurve and default DPI was broken, rendering
labels unreadable.

We'll use proper layouts in Qt5, when the switch finally happens...

Signed-off-by: Stanislaw Halik <sthalik@misaki.pl>
add another TODO item

Signed-off-by: Stanislaw Halik <sthalik@misaki.pl>